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<<Back to DB Administration Main Page How to Upgrade from 11g,12c,18c to 19c DB Upgrade Compatibility Matrix Below is minimum version of the database that can be directly upgraded to Oracle 19c. Source Database Target Database 11.2.0.4 19c 12.1.0.2 19c 12.2.0.1 19c 18.1.0.0 19c NOTE: In this post I will demonstrate the upgrade from 12.1.0.2 to 19c. The steps are same for any other version to 19c upgrade. Upgrading the database from 12.1.0.2 to 19c I will be using DBUA its really easy to use and self explanatory as well as recommended options. It automates many things including upgrading Time zone, gathering dictionary statistics , taking restore RMAN backup or creating restore point , starting the listener with new OH etc. etc. Although DBUA can do many thing its recommended to everything possible that can be done upfront to minimize the overall downtime. General Requirement Ensure All DB Components and objects are valid.

<<Back to Oracle Data Guard Broker Page Oracle Dataguard BystandersFollowRoleChange Property  BystandersFollowRoleChange Valid Values:         ALL| NONE Broker Default:     ALL Lets first look at What is Bystander Database ? The concept of bystander comes only if you have multiple standby databases. Bystander standby database is the standby database that is not directly involved in switchover or failover. In other words all standby databases except failover target database is considered as bystander standby. v$database.fs_failover_status = 'BYSTANDER' can we queried to find the list of bystander databases. The BystandersFollowRoleChange configuration property establishes whether bystander standby databases are evaluated during failover (value = ALL) or after failover (value = NONE). Descriptions of the ALL and NONE options are as follows: ALL - During the failover process, the broker determines whether the bystander standby databases are ahead of or behind the failover ta

<<Back to Oracle Data Guard Broker Page Oracle Dataguard FastStartFailoverPmyShutdown Property  FastStartFailoverPmyShutdown Valid Values:       TRUE| FALSE Broker Default:    TRUE The FastStartFailoverPmyShutdown configuration property causes the primary database to shut down if fast-start failover is enabled and V$DATABASE.FS_FAILOVER_STATUS indicates the primary has been STALLED for longer than FastStartFailoverThreshold seconds. In such a situation, it is likely that the primary has been isolated and a fast-start failover has already occurred. A value of TRUE helps to ensure that an isolated primary database cannot satisfy user queries. DGMGRL> edit configuration set property FastStartFailoverPmyShutdown=TRUE; Property "FastStartFailoverPmyShutdown" updated

<<Back to Oracle Data Guard Broker Page Oracle Dataguard FastStartFailoverAutoReinstate Property  FastStartFailoverAutoReinstate Valid Values:      TRUE| FALSE Broker Default:   TRUE If set to true this property caused the former primary database to automatically re-instantiate and become Standby in case failover occurs. If you want to prevent the automatic re-instantiation set the property value FALSE NOTE: Automatic re-instantiate will only succeed if the database is already configured in flashback mode and necessary archive logs are still present.   DGMGRL> edit configuration set property FastStartFailoverAutoReinstate=FALSE; Property "FastStartFailoverAutoReinstate" updated

Back to Oracle Main Page  Segmentation fault (core dumped) when oracle client 32bit and 64bit Installed on same server Cause : This is an os compiler related issue on RHEL  Solution1: Try relinking  as oracle user go to $ORACLE_HOME/bin ./relink all Solution2: Create an emptry directory  if Solution 1 does not work  1.  Login as root user. 2. Create an empty file /etc/sysconfig/64bit_strstr_via_64bit_strstr_sse2_unaligned

<<Back to Oracle ASM Main Page  Uses of  DISK_REPAIR_TIME and FAILGROUP_REPAIR_TIME Attribute DISK_REPAIR_TIME: DISK_REPAIR_TIME is an attribute for diskgroup and the default value is 3.6Hrs. If ASM unable to perform IO on any disk in the diskgroup it place taht disk offline and wait for time specified in DISK_REPAIR_TIME for the disks be back online. If the disk did not back online with in this time period Oracle ASM then drops that disk from the diskgroup.  SQL> select name,value from v$asm_attribute where group_number=1 and name like '%disk_repair_time%'; NAME                                     VALUE ---------------------------------------- -------------------------------------------------- disk_repair_time                         3.6 h Once you hit a failure and the disk is no more available, ASM marks this disk offline and time starts ticking until disk_repair_time value is reached. If the issue is not fixed and disk is still not available asm drops the disk fro